3-enol ethers of pregnene compounds



3,686,980 3-ENOL ETI-ERS F PREGNENE COMPOUNDS Howard J. Ringold, Shrewshury, Mass., and John Edwards, Mexico City, Mexico, assignors, by mesne assignrnents, to Syntex Corporation, a corporation of Panama No Drawing. Filed Sept. 18, 1961, Ser. No. 133,621

Claims. (Cl. 260-39145).

In the above equation X represents fluoro, chloro, or bromo; X represents hydrogen, chloro or fluoro; Y represents fi-OH, fi-O-CO-CF or. O; acyl represents a conventional acyl group i.e. of a hydrocarbon carboxylic acid of up to 12 carbon atoms; R represents either hydrogen or the same acyl group, and R represents hydrogen, vt-methyl or B-methyl.

The alkoxy group at C-2 comprises any ether group whose hydrocarbon residue is that of any hydrocarbon up to 12 carbon atoms, saturated or unsaturated, of straight or branched chain, cyclic or of a chain combining these configurations, substituted or not with functional groups, and whose group may be an alkyl, aryl or alkylaryl group. Such group can be, for example, the methyl, ethyl, propyl, butyl, isopropyl, hydroxyethyl, acetoxyethyl, phenyl, benzyl, p-methoxyphenyl, ,B-chloropropyl or cyclopentylpropyl group.

The new enol-ethers (II) exhibit very Valuable therapeutic properties, such as anti-inflammatory, glycogenic, thymolytic, catabolic, anti-estrogenic and anti-androgenie effects.

A well known, and generally accepted, method for testing an activity of the cortical type hormones is the determination of the thymolytic effect, which test indicates the anti-arthritic activity in hormones. In the following table we compare by way of example, the thymolytic effect of hydrocortisone 21-acetate with that of the 3- ethyl-enol-ether of 6-chloro-cortisone 21-acetate in adrenalectomized rats, when such compounds were administered by the oral route.

Patented Apr. 23, 1963 From this table it is evident that the thymolytic effect of the ethyl-enol-ether of 6-chloro-oortis0ne ZI-acetate is ten times greater than that of hydrocortisone 21-acetate.

For preparing the novel enol-ethers we treated (I) with a triester of orthoformic acid in mixture with dioxane and in the presence of p-toluenesulfonic acid, to produce the desired enol-ether (II). The ester group at C-21 of (I) may be any ester group, but generally we started from a 21-acetate; in a 6-monohalo-hydrocortisone compound we further protected the llfl-hydroxyl group by esterification with trifluoroacetic acid.

Thus, from the 11-trifluoroacetate-2l-acylate of a 6- halo-hydrocortisone (I; X=F, Cl or Br; X'=H; Y==B-O--COCF R'=H), we obtained the respective 1l-trifluoroacetate-Zl-acylate of the corresponding 6- hal'o-3-a1koxy-A -pregnadien-l1,8,17u,21-triol-20cne (II; X=F, Cl or Br; X=H; Y=,B-O--COCF R=acyl; R =H); from a 21-ester of a 6,9wdihalo-hydrocortisone (I; X=F, C1 or Er; X'=F or Cl; Y=[ -OH; R'=H); we obtained the corresponding 2l-ester of the respective 6,9u-dihalo-3-alkoxy-A -pregnadien 1l[3,l7a,21 triol- 20-one (II; X=F, Cl or Br; X'=F or Cl; Y=fl-OH; R=acyl; R'=H) from an 1l-trifiuoroacetate-Zl-acylate of a 6-halo-16-methyl hydrocortisone (I; X=F, C1 or Br; X=H; Y=,8-OCOCF R'==methy=l); we obtained the respective 1l-triflnoroacetate-Zl-acetate of the corresponding 16-methyl-6-halo-3-a1koxy-A -pregnadien-11B, 17a,2l-triol-20-one (II; X=F, C1 or Br; X=I-I; Y=/3-O-COCF R=acyl; R=methy1); a 21-ester of a 6-halo-cortisone or their corresponding 16otor 166- rnethyl analogs (I; X=F, C1 or Br; X=H; Y=O; R=acyl; -R=H, 0L- or [i-rnethyl) furnished the corresponding 2l-ester of the respective 6-halo-3-alkoxy-A pregnadien-lhJl-di-ol-l1,20-dione (II; X=F, C1 or Br; X=H; Y=O=; R= acyl; R=H, 04- or fi-methyl). A 2l-ester of 6,9-dihalo-cortisone or their 16w or B-rnethyl analogs, (I; XzF, C1 or Br; X -F or Cl; Y=O:; R=H, aor {S-rnethyl) was converted into the corresponding 21-ester of the respective 6,9-dihalo-3-alkoxy- A -pregnadien-17u,21-diol-l1,20'dione (II; X='F, Cl or Br; X"=F or Cl; Y=O=; R=acyl; R:H, ocor ,8- methyl).

The ester group at C-21 or the ester groups at C-11 and 'C21 of the compounds of Formula II mentioned above were hydrolyzed to produce the corresponding free alcohols and then the hydroxyl group at C-2l was reesterified; for these reactions we employed conventional methods; for example, the hydrolysis was effected with dilute methanolic potassium hydroxide and the reesterification at (1-21 was carried out by treatment with the anhydride of a hydrocarbon carboxylic acid of up to 12 carbon atoms, in pyridine solution. The anhydride was derived from an acid which may be saturated or unsaturated, of straight or branched chain, cyclic or mixed cyclic-aliphatic, substituted or not with methoxy, halogen or other groups, to produce, among other 21-esters, the acetates, p-ropionates, butyrates, hemisuccinates, caproates, benzoates, trimethylacetates, phenoxyacet-ates, phenylpropionates, cyclopentylpropionates and ,B-chloropropionates of the compounds of Formula II.

The following preparations illustrate the production of certain of the starting compounds.

PREPARATION 1 A solution of 2 g. of 6a-chlorohydrocortisone 2l-acetate in 12 cc. of anhydrous dioxane was treated with 4.5 cc. of trifiuoroacetic anhydride and the mixture was stirred at room temperature for 18 hours and then poured into a mixture of ice and water; the product was extracted with 4 portions of methylene chloride and the combined extract was washed with water to neutral, dried over anhyisease 3 drous sodium sulfate and evaporated to dryness. The residue crystallized upon trituration with ether. By

chromatography on Washed alumina there was obtained the pure 6oc-chloro-hydrocortisone 11 trifluoroacetate-21- acetate.

PREPARATION 2 In other experiments we applied the method of the previous preparation to any other 21-acylate of the known 6-halo (fluoro, chloro or bromo)-hydrocortisone and to 21-acylates of 16ocor ,B-methyl-hydrocortisone derivatives, to produce the respective 11-trifiuoroacetates-21- acylates. (6-chloro-cortisone and hydrocort'isone compounds are disclosed in U.S. applications Serial Nos. 670,366 and 670,368, filed July 8, 1957; 6-fluoro derivatives of cortisone and hydrocortisone in US. patent application Serial No. 740,550, filed June 9, 1958, now Patent No. 2,934,546; G-ChlOrO-9oc-h8l0 derivatives of cortisone and hydrocortisone in US. patent application Serial No. 741,753, filed June 13, 1958; 6-fluoro-9a-halo derivatives of cortisone and hydrocortisone in US. patent application Serial No. 749,652, filed July 21, 1958, now Patent No. 2,951,840; 6-chloro-16a-methyl hydrocortisone and cortisone as Well as the corresponding 9a-halo derivatives have been disclosed in US. patent application Serial No. 825,665, filed July 8, 1959, 6-chloro-16;3-methyl hydrocortisone and cortisone, and the corresponding 9a-halo derivatives in US. patent application Serial No. 824,200 filed July 1, 1959, now abandoned; 6-fiuoro-16a-methylhydrocortisone and cortisone and the corresponding 9ozhalo derivatives have been described by J. Edwards et al. in J. Am. Chem. Soc. 81, 3156 (1959), and also in our copending application Serial No. 789,242, filed January 27, 1959, and 6-fluoro-16B-methyl-hydrocortisone and cortisone and the corresponding 9a-halo derivatives in our copending application Serial No. 792,962, filed on February 13, 1959; the equivalent 6-bromo compounds may be prepared in the same way as there disclosed.)

The following specific examples serve to illustrate but are not intended to limit the present invention.

Example I To a solution of 2g. of 6a-fluoro-hydrocortisone ll-trifiuoroacetate-Zl-acetate in 14 cc. of anhydrous dioxane there was added. 2 cc. of ethyl orthoformate and 60 mg. of p-toluenesulfonic acid monohydrate and the mixture was stirred for 30 minutes; 5 cc. of pyridine and 200 cc. of Water were then added with stirring and cooling and the product was extracted with ether. The extract was washed with water, dried over anhydrous sodium sulfate and evaporated to dryness. Crystallization of the residue from acetone-hexane afforded 6-fluoro-3-ethoxy-A -pregnadiene-l 1fl,17a,21-triol-20-one 1 1-trifluoroacetate-2l-acetate.

1 g. of the above compound was treated with 10 cc. of a methanol solution containing 100 mg. of potassium hydroxide, with stirring at C. for 2 hours. The mixture was acidified with acetic acid, poured into ice water and the precipitate was collected, washed with water, dried under vacuum and recrystallized from methylene chloride. There was thus obtained 6-fiuoro-3-ethoxy-A -pregnadime-11,8,17a,21-triol-20-one.

A mixture of 500 mg. of the above compound, 5 cc. of pyridine and 0.8 cc. of propionic anhydride was kept overnight at room temperature and then poured into water, heated on the steam bath for half an hour and cooled. The precipitate was filtered, washed with water, dried and recrystallized from acetone-hexane, thus giving 6-fluoro- 3-ethoxy-A -pregnadiene-11[3,17a-21 triol-20-one 21-propionate.

in a similar manner, 6ot-fluoro-16/3-methyl-hydrocortisome 21-acetate-1l-trifluoroacetate gave successively 6 fluoro 16B methyl 3 ethoxy A pregnadiene- 11B,17oc-21-triol-20-one-1 l-trifluoroacetate 2l-acetate, 6 fluoro 165 methyl 3 ethoxy A pregnadiene 11 3, 17a,21-triol-20-one and the 21-propionate.

Example 11 By the same method, 6a,9 -difluoro-hydrocortisone 21- acetate was converted into 6,9a-difluoro-3-'ethoxy-A pregnadiene-l1p,17 t-21-triol-20-one 21 -acetate; the acetate group of the latter was then hydrolyzed and the resulting 6,9ot-dlfi ll0f0 3 ethoxy-h -pregnadiene-115,17u, 21-triol-20-one was reesterified to produce its 21-propionate.

Example III In the method of Example I, there was substituted for the ethyl orthoformate the tripropyl ester of orthoformic acid. There were thus obtained 6-fiuoro-3-propoxy-A pregnadiene 1lB,1'/'a,21 triol-20-one ll-trifluoroacetate- ZI-acetate, 6 fluoro 16/3 methyl-3-propoxy-A -pregnadiene-l1B,17oc-21-triol-20 one 11 -trifiuoroacetate-21-acetate, then the free alcohols and finally their 21-propionates.

Example IV By following the methods described in the previous examples there were prepared the 3-alkyl-enol-ethers of all of the 6-ha1o and 6,90t-dlhalO analogs of hydrocortisone andcortisone comprised in our invention, either in the free form or correspondingly esterified. For example, there Were prepared: 6-chloro-3-ethoxy-A -pregnadiene-1 1;3,17a,21-triol-20-one 1 l-trifluoroacetate-Z l-butyrate then the free 6-chloro-3-ethoxy-A -pregnadiene-11B, 17u,21-triol20-one, and then the latter was esterified at C-21 by reaction with cyclopentylpropionic acid anhydride, thus giving 6-chloro-3-ethoxy-A -pregnadiene-l16, 17u,21-triol-20-one 2l-cyclopentylpropionate. In another experiment there was formed the 3-propyl-enol-ether starting from 6u-bromo-9a-chloro-hydrocortisone 21-acetate, and upon subsequent hydrolysis of the acetate group there was obtained 6-bromo-9a-chloro-3-propoxy-A pregnadiene-I1fl,17a,21-tri01-20-one which was then converted into its 21-butyrate by reaction with butyric anhydride; by the same method 6a,9u-difluoro-cortisone 21- acetate was converted into 6,9a-difluoro-3-ethcxy-a pregnadien-17a,21-.diol-11,20-dione ZI-acetate, then into the free compound and finally into its ZI-trimethylacetate. Among other 21-esters there was also prepared the 21- benzoatcs of these compounds.

Example V To a solution of 1 g. of oz-fluoro-16a-methyl-cortisone acetate in 20 cc. of dioxane there were added 2 cc. of the trimethyl ester of orthoformicacid and 60 mg. of p-toluenesulfonic acid monohydrate. The mixture was stirred at room temperature for 45. minutes, 2 cc. of pyridine were added, and the mixture poured into ice water. The product was then extracted with methylene chloride, the organic extract washed to neutral, dried over anhydrous sodium sulfate and evaporated to dryness. Crystallization from acetone-pentane gave 6-fiuOI'O-16amethyl-B-methoxy A pregnadiene-17a,21-diol-11,20- dione-21-acetate.

By the same method, 6a-chloro-9a-fluoro-16fi-methyl- A -pregnene-17a,21-dio1-3,11,20-trione described in our copending application Serial No. 824,200 and 16a-methyl- 6a,9a-dich1oro-cortisone acetate described in our copending application Serial No. 825,665, were converted respectively into 6-chloro-9a-fiuoro-16B-methyl-3-methoxy-A pregnadiene-17a,21-diol-11,20-dione and 6,9a-dtichloro- 16a-methyl-3-methoxy A pregnadiene-17a,21-diol- 11,20-dione 21-acetate.

Example VI In accordance with the method of Example I, 2.5 g. of 6a-fluoro-16a-methyl-hydrocortisone 11 trifluoroacetate was treated with ethyl orthoformate in dioxane solution and in the presence of p-toluenesulfonic acid, thus producing 6-fluoro-16ot-methyl-A -pregnadiene-11/3,17a,21- triol-20one ll-trifluoroacetate 21-acetate, which in turn was saponified with potassium hydroxide, to give 6-fluoro- 5 16oz methyl-3-ethoxy-A -pregnadiene 11,13,17a,21-triol- 20-one.

Esterification of the latter compound with caproic anhydride in pyridine solution gave the 21-caproate of 6- fluoro-16a-methyl-3-ethoxy-A 4pregnadiene 11,8,17a,21- triol-ZO-one.

Example VII Example II was repeated, but using 6a,9a-difluoro-16amethyl-hydrocortisone 21-acetate and the corresponding 16l3-methyl isomer. There were thus obtained 6,9a-difluoro-l6a-methyl-3-ethoxy-A pregnadiene l1fi,17a,21- triol-20-one-21-acetate; 6,91: difluro-16 8-methyl-3-ethoxy-A -pregnadiene 11,8,17a,21-triol-20-one-2l-acetate, the corresponding free compounds and the corresponding propionates.

Example VIII By following the methods described in Examples I, III and V, the compounds listed below under I were converted into the corresponding alkyl-enol-ethers (II) I-Starting Compound Reagent II-Final Compound 60: fluoro 16a methylisopropyl 6 fiuoro 16 methylcortlsone acetate. orthoformate. 3 isopropoxy A pregnadiene 17a, 21 diol 11, 20 dione 21- acetate. 6a, 9a difiuoro lfiado 6, 91x ditluoro 16a methyl -hydrocortisonemethyl 3 isopropoxy- ZI-acetate. A pregnadiene 11B, 17a,21 triol- -20 one 21-acetate. 6a ehloro 9a fluoro ethyl orthofor- 6 chloro 9a fluoro 16a lfia-methyl-hydrocormate. methyl 3 ethoxy tisone 21 acetate AM pregnadiene 116, 17a, 21 triol 20 one 21-acetate. 6a, 9a dichloro 16B- trlmethyl ester 6, 9a dichloro 16B methyl hydrocrotisone of orthoformic methyl 3 methoxy til-acetate. acid. A pregnadiene 115, 17a, 21 triol 20 one 21-acetate. 6a chloro 16B methyl ethyl orthofor- 6a chloro 16B methyl cortisone 21-acetate. mate. 3 ethoxy A preg nadiene 17a, 21 diol 11,20-dione 21-acetate.

Example IX CHrOR I 325,, Alkoxywherein alkoxy represents a hydrocarbon ether group of up to 12 carbon atoms, Y is selected from the group consisting of =0, -OH and -O-CO-CF3, X is selected from the group consisting of fiuoro, chloro and =bromo, X is selected from the group consisting of hydrogen, fluoro and chloro, R is selected from the group consisting of hydrogen and a hydrocarbon carboxylic :acyl group of up to 12 carbon atoms and R is selected from the group consisting of hydrogen, a methyl and B-methyl.

2. The 3-enol-hydrocarbon-ethers of up to 12 carbon atoms of 6-fiuoro-hydrocortisone.

3. The 3-enol-hydrocanbon-ethers of l6a-methyl-6- fluoro-hydrocortisone.

4. The 3-enol-hydrocanbon ethers of l6B-methyl-6- fluoro-hydrocortisone.

5. The 3-enol-hydrocarbon ethers of up to 12 carbon atoms of 6,9u-difluoro-hydrocortisone.

6. The 3-enol-hydrocar bon ethers of up to 12 carbon atoms of 6-chloro-9a-fluoro-hydrocortisone.

7. The 3-enol-hydrocanbon ethers of 6-fluoro-cortisone.

8. The 3-cnol-hydrocarbon ethers of 6-chloro-cortisone.

9. The 3-enol-ethers of 6-chloro-9a-fluoro-cortisone.

10. The 21-hydrocarbon canboxylic acid esters of up to 12 carbon atoms of the 3-enol hydrocarbon ethers of up to 12 carbon atoms of 6-fluoro-hydrocortisone.

11. The 2l-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of the 3-enol-hydrocarbon ethers of up to 12 carbon atoms of 6-chloro-hydrocortisone.

12. The 2l-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of the 3-enol-hydrocarbon ethers of up to 1-2 carbon atoms of 6,90:-difluoro-hydrocortisone.

13. The ZI-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of the 3-enol-hydrocarbon ethers of up to 12 carbon atoms of '6-ch1oro-9ot-fluoro-hydrocortisone.

14. The 21-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of the S-enol-hydrocarbon ethers of up to 12 carbon atoms of 6-fluoro-cortisone.

15. The 2-l-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of the 3-enol-hydrocarbon ethers of up to 12 carbon atoms of 6-chloro-cortisone.

16. The 21-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of the 3-enol-hydrocarbon ethers of up to 12 carbon atoms of 6,9u-difluoro-cortisone.

17. The 21-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of 6-Chl0l'09a-flll0IO-C0rti50l16.

18. The 3-enol-hydrocarbon-ethers of 6,9a-diflu010- 1-6ot-methyl-hydrocortisone.

1-9. The 3-enol-hydrocarbon-ethers of -6a-chloro-16l3- methyl-cortisone.

20. The -21-hydrocarbon carboxylic acid esters of up to 12 carbon atoms of the S-enol-hydrocarbon ethers of up to 12 carbon atoms of 6a,9a-dichloro-165-methylhydrocortisone.

Koster Nov. 21, 1-944 Ercoli et al Aug. 12, 1958 

1. A COMPOUND OF THE FOLLOWING FORMULA: 